Abstract Although various measurement techniques have been applied to both qualitative and quantitative evaluation for the electromagnetic shielding performance of braided-shield power cables, the existing measurements cannot directly assess the low-frequency shielding performance (typically below 100 kHz) due to factors such as ground-loop effects and dynamic range problem in measurement. To solve these, an improved shield reduction factor method, based on gain (T/R) rather than scattering parameters, is proposed to evaluate the shielding performance of braided-shield power cables from 25 Hz to 1 MHz. In this work, we highlight the implementation of measurement setup to avoid the effects of ground-loop and stray electromagnetic field. Meanwhile, the test cell is simplified according to the definition of the shield reduction factor in order to obtain the gain (T/R) parameters, which can be used to calculate transfer impedance as well. From the measurements we present more intuitive evaluation of shielding behavior of braided-shield power cables at low frequency regimes, and showcase a detailed comparative discussion between transfer impedance and shield reduction factor. The proposed shield reduction factor method is expected to be a useful way for the evaluation of the low frequency shielding performance of braided-shield cables.

中文翻译：

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低频状态下编织屏蔽电力电缆的电磁屏蔽性能测量

摘要 尽管各种测量技术已应用于编织屏蔽电力电缆电磁屏蔽性能的定性和定量评估，但由于接地等因素，现有的测量无法直接评估低频屏蔽性能（通常低于 100 kHz）。测量中的回路效应和动态范围问题。为了解决这些问题，提出了一种基于增益 (T/R) 而不是散射参数的改进的屏蔽折减系数方法来评估 25 Hz 至 1 MHz 编织屏蔽电力电缆的屏蔽性能。在这项工作中，我们强调了测量设置的实施，以避免接地回路和杂散电磁场的影响。同时，根据屏蔽衰减系数的定义简化测试单元以获得增益 (T/R) 参数，该参数也可用于计算传输阻抗。根据测量结果，我们更直观地评估了编织屏蔽电力电缆在低频状态下的屏蔽行为，并展示了传输阻抗和屏蔽折减系数之间的详细比较讨论。所提出的屏蔽折减系数法有望成为评估编织屏蔽电缆低频屏蔽性能的有用方法。并展示传输阻抗和屏蔽衰减系数之间的详细比较讨论。所提出的屏蔽折减系数法有望成为评估编织屏蔽电缆低频屏蔽性能的有用方法。并展示传输阻抗和屏蔽衰减系数之间的详细比较讨论。所提出的屏蔽折减系数法有望成为评估编织屏蔽电缆低频屏蔽性能的有用方法。